More flexible hydrothermal units

[yalinli2]

@jiananf2 FYI, I'm hoping to update the hydrothermal units so that they are more flexible (i.e., not written in the context of sludge/WWTP, not necessarily using the predictive models, etc.). In the future, I probably will move your hydrothermal/hydroprocessing units to the htl module in EXPOsan and put the new units (still largely based on your codes) in QSDsan.

I'm using this issue to document the changes.

[yalinli2]

In Hydrocracking, the two hxs are defined as heat_exchanger_H2 and heat_exchanger_oil, is the name correct in defining the auxiliary units? I tried to change the names but it'll trigger the error, so I'm suspecting that those hxs were not included in the simulation. Also not sure if their costs were included.

QSDsan/qsdsan/sanunits/_hydroprocessing.py

Line 78 in 9afc033

auxiliary_unit_names=('compressor','heat_exchanger',)

[yalinli2]

@jiananf2 why are the products from Hydrocracking/Hydrotreating in gas phase?

QSDsan/qsdsan/sanunits/_hydroprocessing.py

Line 167 in 9afc033

hc_out.phase = 'g'

QSDsan/qsdsan/sanunits/_hydroprocessing.py

Line 421 in 9afc033

ht_out.phase = 'g'

[yalinli2]

@jiananf2 why are the products from Hydrocracking/Hydrotreating in gas phase?

QSDsan/qsdsan/sanunits/_hydroprocessing.py

Line 167 in 9afc033

hc_out.phase = 'g'

QSDsan/qsdsan/sanunits/_hydroprocessing.py

Line 421 in 9afc033

ht_out.phase = 'g'

I think I know the reason, it's because of the mass allocation after vle... I'll just set the phase to be the same as the influent oil (g anyway)

[jiananf2]

In Hydrocracking, the two hxs are defined as heat_exchanger_H2 and heat_exchanger_oil, is the name correct in defining the auxiliary units? I tried to change the names but it'll trigger the error, so I'm suspecting that those hxs were not included in the simulation. Also not sure if their costs were included.

QSDsan/qsdsan/sanunits/_hydroprocessing.py

Line 78 in 9afc033

auxiliary_unit_names=('compressor','heat_exchanger',)

After I changed the names, HXN had an error. This is because the heat is not balanced. The hydrotreating and hydrocracking reactions release heat. I just increased the output temperatures in the current model without modeling the released heat.

[yalinli2]

@jiananf2 OK thanks for letting me know, I don't think the costs (not sure of the utilities, I didn't check) were included.